In the W-CDMA (Wide band Code Division Multiple Access) communicating system which is compliant with the 3GPP (3rd Generation Partnership Project) which is currently being standardized, the HSDPA (High Speed Downlink Packet Access) has been proposed as a technique for realizing a high speed down link.
Meanwhile, since the receiving quality of received data, whose encoding ratio is high like the HSDPA, is easily influenced by a multi-path interference, it is necessary to provide the wireless communicating apparatus realizing the HSDPA with an interference canceller which can reduce the multi-path interference.
However, the interference canceller includes such a disadvantage that the ability can not be realized depending on a propagation channel condition, and also includes such a weak point that the decoding quality becomes worse than that of the conventional receiving method, in which the interference canceller is not used, depending on the propagation channel condition.
From the above description, it is necessary to communicate via wireless as separating, depending on an electric wave channel condition, a receiving method, such as the interference canceller, which needs to reduce the multi-path interference, a receiving method which does not need to reduce the multi-path interference without using the interference canceller, and the like.
Meanwhile, there exists a patent document which has been applied before the present invention, and discloses a wireless communicating apparatus which includes estimating means for estimating a signal propagation environment, and selecting means for selecting a signal receiving method according to the estimated propagation environment from the two or more receiving methods including at least the liner equalization, and enables the total system throughput to be improved (for example, refer to Patent Document 1).
There exists a document disclosing a geometry measuring method which is a geometry measuring method used by a wireless receiving apparatus in a wireless communicating system in a cellular method, includes a interfered signal electric power measuring step for measuring the electric power of an interfered signal included in a received signal for each path, an adding step for adding N paths of the interfered signal electric power measured for each path, a path excluded interfered signal electric power level measuring step for measuring the electric power of the interfered signal, which is not influenced by the path, but is included in the received signal, an own cell interfered signal electric power calculating step for calculating own cell interfered signal electric power by subtracting the adding result at the adding step from a value obtained by N-multiplying the measured path excluded interfered signal electric power, other cell interfered signal/noise electric power calculating step for calculating an added value of the electric power of an other cell interfered signal and a noise by subtracting the calculated own cell interfered signal electric power from the measured path excluded interfered signal electric power, and a geometry calculating step for calculating the geometry by dividing the calculated own cell interfered signal electric power by the calculated added value of the electric power of the other cell interfered signal and the noise, and can conveniently generate the geometry under the propagation environment in which the multi-path is formed, in which it can be easily determined whether to RAKE-receive the received signal, or to adaptively-receive the received signal by using an adaptive equalizer, the interference canceller, and the like in the wireless receiving apparatus (for example, refer to Patent Document 2).    Patent Document 1: Japanese Patent Laid Open Publication No. 2004-159284    Patent Document 2: Japanese Patent Laid Open Publication No. 2005-303952